Hi,
If by giant kod you mean giant shark then their cheap radiolink TX/RX's are okay, not the best quality in the world but they will work. I would advise going spectrum. a DX5e won't be that much more and will be far, far better quality.
Best bolt the sabertooth, and shock mount it. Those things are delicate! RX's can be zip tied or probbably held down with the sticky foam.
only the Robochallange featherweight events such as the champs have spinners.
removable links are normally just some deans connectors , not hard at all to make. or you can buy pre made ones and mounts if you so wish from Robochallange. LED's are just LED's. you can buy them from Technobots or Gimson robotics.
events calender is on the FRA homepage.

Hope this is vaguely helpful.